During the polymerase chain reaction, the two dna strands are separated at 95°c, after which the reaction mixture is cooled to 54°c to allow the primers to hybridize to the dna strands. why do primer‑template hybrids form instead of parent dna duplexes?

Aperson with age is more likely to catch diseases that healthy people usually don’t catch.what are these infections called?

Which of the following describes a negative feedback loop? when the heart rate is too high, the body sends hormones that continually increase the heart rate higher. when a pregnant woman is in labor, the body sends hormones that increase the intensity of contractions, which then increases the secretion of the same hormones. when blood sugar is too low, the body sends hormones that raise blood sugar until it reaches a typical level and hormone secretion slows. when a person is jogging, the body sends hormones that continually decrease the rate of oxygen supply to the legs.

Which of these is not a nucleotide base found in dna?